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<h2>CL-FAD - A portable pathname library for Common Lisp</h2>

<blockquote>
<br>&nbsp;<br><h3><a name=abstract class=none>Abstract</a></h3>

CL-FAD (for "<font color=red>F</font>iles <font color=red>a</font>nd
<font color=red>D</font>irectories") is a thin layer atop Common
Lisp's standard pathname functions.  It is intended to provide some
unification between current CL implementations on Windows, OS X,
Linux, and Unix.  Most of the code was written by Peter Seibel for his book <a href="http://www.gigamonkeys.com/book/"><em>Practical Common Lisp</em></a>.

<p>

CL-FAD comes with a <a
href="http://www.opensource.org/licenses/bsd-license.php">BSD-style
license</a> so you can basically do with it whatever you want.

<p>
<font color=red>Download shortcut:</font> <a href="https://github.com/edicl/cl-fad/archive/master.zip">https://github.com/edicl/cl-fad/archive/master.zip</a>.
</blockquote>

<br>&nbsp;<br><h3><a class=none name="contents">Contents</a></h3>
<ol>
  <li><a href="#download">Download and installation</a>
  <li><a href="#implementations">Supported Lisp implementations</a>
  <li><a href="#dictionary">The CL-FAD dictionary</a>
  <ol>
    <li><a href="#querying">Querying files, directories and pathnames</a>
      <ol>
        <li><a href="#directory-exists-p"><code>directory-exists-p</code> [function]</a>
        <li><a href="#directory-pathname-p"><code>directory-pathname-p</code> [function]</a>
        <li><a href="#file-exists-p"><code>file-exists-p</code> [function]</a>
        <li><a href="#pathname-absolute-p"><code>pathname-absolute-p</code> [function]</a>
        <li><a href="#pathname-equal"><code>pathname-equal</code> [function]</a>
        <li><a href="#pathname-relative-p"><code>pathname-relative-p</code> [function]</a>
        <li><a href="#pathname-root-p"><code>pathname-root-p</code> [function]</a>
    </ol> </li>
    <li><a href="#manipulating">Manipulating pathnames</a>
      <ol>
        <li><a href="#canonical-pathname"><code>canonical-pathname</code> [function]</a>
        <li><a href="#merge-pathnames-as-directory"><code>merge-pathnames-as-directory</code> [function]</a>
        <li><a href="#merge-pathnames-as-file"><code>merge-pathnames-as-file</code> [function]</a>
        <li><a href="#pathname-as-directory"><code>pathname-as-directory</code> [function]</a>
        <li><a href="#pathname-as-file"><code>pathname-as-file</code> [function]</a>
        <li><a href="#pathname-directory-pathname"><code>pathname-directory-pathname</code> [function]</a>
        <li><a href="#pathname-parent-directory"><code>pathname-parent-directory</code> [function]</a>
    </ol> </li>
    <li><a href="#traversing">Traversing directories</a>
      <ol>
        <li><a href="#list-directory"><code>list-directory</code> [function]</a>
        <li><a href="#walk-directory"><code>walk-directory</code> [function]</a>
    </ol> </li>
    <li><a href="#temporary-files">Temporary Files</a>
      <ol>
        <li><a href="#open-temporary"><code>open-temporary</code> [function]</a>
        <li><a href="#with-output-to-temporary-file"><code>with-output-to-temporary-file</code> [macro]</a>
        <li><a href="#with-open-temporary-file"><code>with-open-temporary-file</code> [macro]</a>
        <li><a href="#star-default-template-star"><code>*default-template*</code> [variable]</a>
        <li><a href="#cannot-create-temporary-file"><code>cannot-create-temporary-file</code> [condition]</a>
        <li><a href="#invalid-temporary-pathname-template"><code>invalid-temporary-pathname-template</code> [condition]</a>
        <li><a href="#missing-temp-environment-variable"><code>missing-temp-environment-variable</code> [condition]</a>
        <li><a href="#lp-host-temporary-files"><code>temporary-files</code> [logical pathname host]</a>
      </ol>
    </li>
    <li><a href="#modifying">Modifying the file system</a>
      <ol>
        <li><a href="#copy-file"><code>copy-file</code> [function]</a>
        <li><a href="#copy-stream"><code>copy-stream</code> [function]</a>
        <li><a href="#delete-directory-and-files"><code>delete-directory-and-files</code> [function]</a>
    </ol> </li>
    <li><a href="#package-path"><code>path</code> [package]</a>
  </ol>
  <li><a href="#ack">Acknowledgements</a>
</ol>



<br>&nbsp;<br><h3><a class=none name="download">Download and installation</a></h3>

CL-FAD together with this documentation can be downloaded from <a
href="http://weitz.de/files/cl-fad.tar.gz">http://weitz.de/files/cl-fad.tar.gz</a>. The
current version is 0.7.1.
<p>
CL-FAD comes with simple system definitions for <a
href="http://www.cliki.net/mk-defsystem">MK:DEFSYSTEM</a> and <a
href="http://www.cliki.net/asdf">asdf</a> so you can either adapt it
to your needs or just unpack the archive and from within the CL-FAD
directory start your Lisp image and evaluate the form
<code>(mk:compile-system&nbsp;&quot;cl-fad&quot;)</code> - or <code>(asdf:oos&nbsp;'asdf:load-op&nbsp;:cl-fad)</code> for asdf - which should compile and load the whole
system.
Installation via <a
href="http://www.cliki.net/asdf-install">asdf-install</a> should as well
be possible.  Plus, there are ports
for <a href="http://www.gentoo.org/proj/en/common-lisp/index.xml">Gentoo Linux</a> thanks to Matthew Kennedy
and for <a href="http://packages.debian.org/cgi-bin/search_packages.pl?keywords=cl-fad&amp;searchon=names&amp;subword=1&amp;version=all&amp;release=all">Debian Linux</a> thanks to Ren&eacute; van Bevern.
<p>
If for some reason you can't or don't want to use MK:DEFSYSTEM or asdf you
can just <code>LOAD</code> the file <code>load.lisp</code>.
<p>
The latest version of the source code lives in the github repository <a href="https://github.com/edicl/cl-fad">edicl/cl-fad</a>

If you want to send patches, please <a href="http://weitz.de/patches.html">read this first</a>.

<br>&nbsp;<br><h3><a class=none name="implementations">Supported Lisp implementations</a></h3>

<p>
The following Common Lisp implementations are currently supported:
<ul>
<li><a href="http://armedbear.org/abcl.html">Armed Bear Common Lisp</a>
<li><a href="http://www.cons.org/cmucl/">CMUCL</a>
<li><a href="http://www.cormanlisp.com/">Corman Common Lisp</a>
<li><a href="http://ecls.sf.net/">ECL</a>
<li><a href="http://www.franz.com/products/allegrocl/">Franz AllegroCL</a>
<li><a href="http://clisp.cons.org/">GNU CLISP</a>
<li><a href="http://www.lispworks.com/">LispWorks</a>
<li><a href="http://www.digitool.com/">Macintosh Common Lisp</a>
<li><a href="http://openmcl.clozure.com/">OpenMCL</a>
<li><a href="http://www.scieneer.com/scl/">Scieneer Common Lisp</a>
<li><a href="http://sbcl.sourceforge.net/">Steel Bank Common Lisp</a>
</ul>

I'll gladly accepts patches to make CL-FAD work on other platforms.


<br>&nbsp;<br><h3><a class=none name="dictionary">The CL-FAD dictionary</a></h3>

<h4><a class=none name="querying">Querying files, directories and pathnames</a></h4>

<p><br>[Function]
<br><a class=none name="directory-exists-p"><b>directory-exists-p</b> <i> pathspec </i> =&gt; <i> generalized-boolean</i></a>

<blockquote><br>
Checks whether the file named by the <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_p.htm#pathname_designator">pathname designator</a> <code><i>pathspec</i></code>
exists and if it is a directory.  Returns its <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_t.htm#truename">truename</a> if this is the
case, <code>NIL</code> otherwise.  The truename is returned in <em>directory form</em> as if
by <a href="#pathname-as-directory"><code>PATHNAME-AS-DIRECTORY</code></a>.
</blockquote>

<p><br>[Function]
<br><a class=none name="directory-pathname-p"><b>directory-pathname-p</b> <i> pathspec </i> =&gt; <i> generalized-boolean</i></a>

<blockquote><br>
Returns <code>NIL</code> if <code><i>pathspec</i></code> (a <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_p.htm#pathname_designator">pathname designator</a>) does not designate
a directory, <code><i>pathspec</i></code> otherwise.  It is irrelevant whether the file or
directory designated by <code><i>pathspec</i></code> does actually exist.
</blockquote>

<p><br>[Function]
<br><a class=none name="file-exists-p"><b>file-exists-p</b> <i> pathspec </i> =&gt; <i> generalized-boolean</i></a>

<blockquote><br>
Checks whether the file named by the <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_p.htm#pathname_designator">pathname designator</a> <code><i>pathspec</i></code>
exists and returns its <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_t.htm#truename">truename</a> if this is the case, <code>NIL</code> otherwise.
The truename is returned in "canonical" form, i.e. the truename of a
directory is returned in <em>directory form</em> as if by <a href="#pathname-as-directory"><code>PATHNAME-AS-DIRECTORY</code></a>.
</blockquote>

<p><br>[Function]<br><a class=none name='pathname-absolute-p'><b>pathname-absolute-p</b> <i>a</i> =&gt; <i>result</i></a>
<blockquote>
<p>Returns true if <code><i>a</i></code> is an absolute pathname. This simply
tests if <code><i>a</i></code>&#039;s directory list starts with <code>:ABSOLUTE</code></p>
</blockquote>

<p><br>[Function]<br><a class=none name='pathname-equal'><b>pathname-equal</b> <i>a b</i> =&gt; <i>result</i></a>
<blockquote>

<p>Returns <em>true</em> if <code><i>a</i></code> and <code><i>b</i></code>
represent the same pathname. This function does not access the
filesystem, it only looks at the components of the two pathnames to
test if they are the same (though by passing both <code><i>a</i></code>
and <code><i>b</i></code> to probe-file one can make this function test for
file &#039;sameness&#039;.</p>

<p>Equality is defined as:</p>

<ul>
  <li>strings that are <code>string=</code>
  <li>symbols (including <code>nil</code> and keywords) which are <code>eql</code>
  <li>lists of the same length with equal (as per these rules) elements.
</ul>

<p>If any of these tree conditions is false for any of the components in
<code><i>a</i></code> and <code><i>b</i></code> then <code><i>a</i></code>
and <code><i>b</i></code> are different, otherwise they are the same.</p>

<p><em>NB:</em> This function does not convert name strings to pathnames. So
&quot;foo.txt&quot; and #P&quot;foo.txt&quot; are different pathnames.</p>

</blockquote>

<p><br>[Function]<br><a class=none name='pathname-relative-p'><b>pathname-relative-p</b> <i>a</i> =&gt; <i>result</i></a>
<blockquote>
<p>Returns true if <code><i>a</i></code> is a relative pathname. This simply
tests if <code><i>a</i></code>&#039;s directory starts
with <code>:RELATIVE</code>.</p>
</blockquote>

<p><br>[Function]<br><a class=none name='pathname-root-p'><b>pathname-root-p</b> <i>a</i> =&gt; <i>result</i></a>
<blockquote>
<p>Returns <em>true</em> if <code><i>pathname</i></code> is the root
directory (in other words, a directory which is its own parent).</p>
</blockquote>

<h4><a class=none name="manipulating">Manipulating pathnames</a></h4>

<p><br>[Function]<br><a class=none name='canonical-pathname'><b>canonical-pathname</b> <i>pathname</i> =&gt; <i>result</i></a>
<blockquote>
<p>Remove reduntant information from PATHNAME.</p>

<p>This simply walks down <code>PATHNAME</code>&#039;s
pathname-directory and drops &quot;.&quot; directories, removes :back
and its preceding element.</p>

<p>NB: This function does not access the filesystem, it only looks at the
values in the pathname and works on their known (or assumed)
meanings.</p>

<p>NB: Since this function does not access the filesystem it will only
remove <code>:BACK</code> elements from the path (not <code>:UP</code>
elements). Since some lisps, ccl/sbcl/clisp convert &quot;..&quot; in
pathnames to <code>:UP</code>, and not <code>:BACK</code>, the actual
utility of the function is limited.</p>
</blockquote>

<p><br>[Function]<br><a class=none name='merge-pathnames-as-directory'><b>merge-pathnames-as-directory</b> <i><tt>&amp;rest</tt> pathnames</i> =&gt; <i>result</i></a>
<blockquote>
<p>Given a list of, probably relative, pathnames returns a single
directory pathname containing the logical concatenation of them all.</p>

<p>The returned value is the current directory if one were to cd into
each of <code><i>pathnames</i></code> in order. For this reason an
absolute pathname will, effectively, cancel the affect of any previous
relative pathnames.</p>

<p>The returned value&#039;s defaults are taken from the first element of
<code><i>pathnames</i></code> (host, version and device).</p>

<p><em>NB:</em> Since this function only looks at directory names the name and
type of the elements of <code><i>pathnames</i></code> are ignored. Make sure to properly
use either trailing #\/s, or <a href="#pathname-as-directory">pathname-as-directory</a>, to get the
expected results.</p>

<p>Examples:</p>

<pre>
  (merge-pathnames-as-directory #P&quot;foo/&quot; #P&quot;bar/&quot;) == #P&quot;foo/bar/&quot;

  (merge-pathnames-as-directory #P&quot;foo/&quot; #P&quot;./bar/&quot;) == #P&quot;foo/./bar/&quot;

  (merge-pathnames-as-directory #P&quot;foo/&quot; #P&quot;/bar/&quot;) == #P&quot;/bar/&quot;

  (merge-pathnames-as-directory #P&quot;foo/&quot; #P&quot;/bar/&quot; #P&#039;quux/file.txt) == #P&quot;/bar/quux/&quot;
</pre>

</blockquote>

<p><br>[Function]<br><a class=none name='merge-pathnames-as-file'><b>merge-pathnames-as-file</b> <i><tt>&amp;rest</tt> pathnames</i> =&gt; <i>result</i></a>
<blockquote>
<p>Given a list of, probably relative, pathnames returns a single
filename pathname containing the logical concatenation of them all.</p>

<p>The returned value&#039;s defaults are taken from the first element of
<code><i>pathnames</i></code> (host, version and device). The returned
values&#039;s name, type and version are taken from the last element
of <code><i>pathnames</i></code>. The intervening elements are used only for
their pathname-directory values.</p>

Examples:

<pre>
  (merge-pathnames-as-file #P&quot;foo/&quot; #P&quot;bar.txt&quot;) == #P&quot;foo/bar.txt&quot;

  (merge-pathnames-as-file #P&quot;foo/&quot; #P&quot;./bar.txt&quot;) == #P&quot;foo/./bar.txt&quot;

  (merge-pathnames-as-file #P&quot;foo/&quot; #P&quot;/bar/README&quot;) == #P&quot;/bar/README&quot;

  (merge-pathnames-as-file #P&quot;/foo/&quot; #P&quot;/bar/&quot; #P&#039;quux/file.txt) == #P&quot;/bar/quux/file.txt&quot;
</pre>

</blockquote>

<p><br>[Function]
<br><a class=none name="pathname-as-directory"><b>pathname-as-directory</b> <i> pathspec </i> =&gt; <i> pathname</i></a> 
<blockquote><br>
Converts the <em>non-wild</em> <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_p.htm#pathname_designator">pathname designator</a> <code><i>pathspec</i></code> to <em>directory form</em>, i.e. it returns a <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_p.htm#pathname">pathname</a> which would return a <em>true</em> value if fed to <a href="#directory-pathname-p"><code>DIRECTORY-PATHNAME-P</code></a>.
</blockquote>

<p><br>[Function]
<br><a class=none name="pathname-as-file"><b>pathname-as-file</b> <i> pathspec </i> =&gt; <i> pathname</i></a>

<blockquote><br>
Converts the <em>non-wild</em> <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_p.htm#pathname_designator">pathname designator</a> <code><i>pathspec</i></code> to <em>file form</em>, i.e. it returns a <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_p.htm#pathname">pathname</a> which would return a <code>NIL</code> value if fed to <a href="#directory-pathname-p"><code>DIRECTORY-PATHNAME-P</code></a>.
</blockquote>

<p><br>[Function]<br><a class=none name='pathname-directory-pathname'><b>pathname-directory-pathname</b> <i>pathname</i> =&gt; <i>result</i></a>
<blockquote>
<p>Returns a complete pathname representing the directory of
<code><i>pathname</i></code>. If <code><i>pathname</i></code> is
already a directory pathname
(<code>name</code> <code>nil</code>, <code>type</code>
<code>nil</code>) returns a pathname equal (as
per <a href="#pathname-equal">pathname-equal</a>) to it.</p>
</blockquote>

<p><br>[Function]<br><a class=none name='pathname-parent-directory'><b>pathname-parent-directory</b> <i>pathname</i> =&gt; <i>result</i></a>
<blockquote>

<p>Returns a pathname which would, by name at least,
contain <code><i>pathname</i></code> as one of its direct
children. Symlinks can make the parent/child relationship a like
opaque, but generally speaking the value returned by this function is
a directory name which contains <code><i>pathname</i></code>.</p>

<p>The root directory, #P&quot;/&quot;, is its own parent. The parent
directory of a filename is the parent of the filename&#039;s
dirname.</p>

</blockquote>

<h4><a class=none name="traversing">Traversing directories</a></h4>

<p><br>[Function]
<br><a class=none name="list-directory"><b>list-directory</b> <i> dirname <tt>&amp;key</tt> follow-symlinks</i> =&gt; <i> list</i></a>

<blockquote><br>
<p>
Returns a <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_f.htm#fresh">fresh</a> list of pathnames corresponding to
all files within the directory named by the non-wild <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_p.htm#pathname_designator">pathname designator</a> <code><i>dirname</i></code>.  The pathnames of sub-directories are returned in
<em>directory form</em> - see <a href="#pathname-as-directory"><code>PATHNAME-AS-DIRECTORY</code></a>.
</p>
<p>
  If <code><i>follow-symlinks</i></code> is true (which is the
  default), then the returned list contains truenames (symlinks will
  be resolved) which essentially means that it might also return files
  from <b>outside</b> the directory.  This works on all platforms.
</p>
<p>
  When <code><i>follow-symlinks</i></code> is <code>NIL</code>, it should return the actual directory
  contents, which might include symlinks. (This is currently implemented only on SBCL and CCL.)
</p>
</blockquote>

<p><br>[Function]
<br><a class=none name="walk-directory"><b>walk-directory</b> <i> dirname fn <tt>&amp;key</tt> directories if-does-not-exist test follow-symlinks</i> =&gt; |</a>

<blockquote><br>
<p>
  Recursively applies the function designated by the <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_f.htm#function_designator">function 
  designator</a> <code><i>fn</i></code> to all files within the directory named 
  by the non-wild <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_p.htm#pathname_designator">pathname 
  designator</a> <code><i>dirname</i></code> and all of its sub-directories. <code><i>fn</i></code> 
  will only be applied to files for which the function <code><i>test</i></code> 
  returns a <em>true</em> value. (The default value for <code><i>test</i></code> 
  always returns <em>true</em>.) If <code><i>directories</i></code> is not <code>NIL</code>, 
  <code><i>fn</i></code> and <code><i>test</i></code> are applied to directories 
  as well. If <code><i>directories</i></code> is <code>:DEPTH-FIRST</code>, <code><i>fn</i></code> 
  will be applied to the directory's contents first. If <code><i>directories</i></code> 
  is <code>:BREADTH-FIRST</code> and <code><i>test</i></code> returns <code>NIL</code>, the 
  directory's content will be skipped.  <code><i>if-does-not-exist</i></code> must 
  be one of <code>:ERROR</code> or <code>:IGNORE</code> where <code>:ERROR</code> 
  (the default) means that an error will be signaled if the directory <code><i>dirname</i></code> 
  does not exist.
</p>
<p>
  If <code><i>follow-symlinks</i></code> is true (which is
  the default), then your callback will receive truenames.  Otherwise
  you should get the actual directory contents, which might include
  symlinks.  This might not be supported on all platforms.  See
  <a href="#list-directory"><code>LIST-DIRECTORY</code></a>.
</p>
</blockquote>

<h4><a class=none name="temporary-files">Temporary Files</a></h4>

<h5>Synopsis</h5>

    <p>
      Create a temporary file and return its name:
<pre>CL-USER&gt; (temporary-file:<code xmlns=""><a href="#with-output-to-temporary-file">with-output-to-temporary-file</a></code> (foo)
           (print "hello" foo))
#P"/var/folders/Yu/YuNMNBNPGoqs9G-1Wmj1dk+++TI/-Tmp-/temp-yjck024x"</pre>
    </p>
    <p>
      Create a temporary file, read and write it, have it be deleted
      automatically:
<pre>CL-USER&gt; (temporary-file:<code xmlns=""><a href="#with-open-temporary-file">with-open-temporary-file</a></code> (foo :direction :io)
           (print "hello" foo)
           (file-position foo 0)
           (read foo))
"hello"</pre>
    </p>
  
  <h5><a class="none" name="default-temporary-directory">Default temporary file directory</a></h5>
    By default, temporary files are created in a system specific
    directory that defaults based on operating system conventions.  On
    Unix and Unix-like systems, the directory <tt>/tmp/</tt> is used
    by default.  It can be overridden by setting the <tt>TMPDIR</tt>
    environment variable.  On Windows, the value of the environment
    variable <tt>TEMP</tt> is used.  If it is not set, temporary file
    creation will fail.
  
  <h5><a class="none" name="defining-temporary-directory">Defining the temporary file directory</a></h5>
    <p>
      The Lisp application can set the default directory in which
      temporary files are created by the way of the
      <code xmlns=""><a href="#temporary-files">temporary-files</a></code> logical pathname host:

<pre>(setf (<a xmlns="" href="http://www.lispworks.com/documentation/HyperSpec/Body/f_logica.htm">logical-pathname-translations</a> "<code xmlns=""><a href="#temporary-files">temporary-files</a></code>") '(("*.*.*" "/var/tmp/")))</pre>

      This would set the directory for temporary files to
      <tt>/var/tmp/</tt>.  For more information about logical
      pathnames, please refer to <a href="http://www.cs.cmu.edu/afs/cs/project/ai-repository/ai/html/cltl/clm/node208.html#SECTION002715000000000000000">Common
      Lisp the Language, 2nd Edition</a> and the <a href="http://clhs.lisp.se/Body/19_.htm">Common Lisp
      HyperSpec</a>.
    </p>
    <p>
      Physical path names have restrictions regarding the permitted
      character in file names.  If these restrictions conflict with
      your desired naming scheme, you can pass a physical pathname as
      TEMPLATE parameter to the temporary file generation function.
    </p>
    <p>
      Here are a few examples:
<pre>CL-USER&gt; (<a xmlns="" href="http://www.lispworks.com/documentation/HyperSpec/Body/f_logica.htm">logical-pathname-translations</a> "temporary-files")
(("*.*.*" #P"/var/folders/Yu/YuNMNBNPGoqs9G-1Wmj1dk+++TI/-Tmp-/"))
CL-USER&gt; (temporary-file:<code xmlns=""><a href="#with-open-temporary-file">with-open-temporary-file</a></code> (foo)
           (<a xmlns="" href="http://www.lispworks.com/documentation/HyperSpec/Body/f_pn.htm">pathname</a> foo))
#P"/var/folders/Yu/YuNMNBNPGoqs9G-1Wmj1dk+++TI/-Tmp-/temp-6rdqdkd1"</pre>

      This used the temporary directory established in the TMPDIR
      environment variable, by the way of the definition of the
      temporary-files logical host definition.

<pre>CL-USER&gt; (temporary-file:<code xmlns=""><a href="#with-open-temporary-file">with-open-temporary-file</a></code> (foo :template "/tmp/file.with.dots.in.name.%.txt")
           (<a xmlns="" href="http://www.lispworks.com/documentation/HyperSpec/Body/f_pn.htm">pathname</a> foo))
#P"/tmp/file.with.dots.in.name.2EF04KUJ.txt"</pre>

      Here, a physical pathname was used for the
      <code xmlns=""><i>:template</i></code> keyword argument so that a
      filename containing multiple dots could be generated.

<pre>CL-USER&gt; (temporary-file:<code xmlns=""><a href="#with-open-temporary-file">with-open-temporary-file</a></code> (foo :template "temporary-files:blah-%.txt")
           (<a xmlns="" href="http://www.lispworks.com/documentation/HyperSpec/Body/f_pn.htm">pathname</a> foo))
#P"/var/folders/Yu/YuNMNBNPGoqs9G-1Wmj1dk+++TI/-Tmp-/blah-72mj450d.txt"</pre>

      This used the temporary-files logical pathname host, but changed
      the filename slightly.

<pre>CL-USER&gt; *default-pathname-defaults*
#P"/Users/hans/"
CL-USER&gt; (temporary-file:<code xmlns=""><a href="#with-open-temporary-file">with-open-temporary-file</a></code> (foo :template "blah-%.txt")
           (<a xmlns="" href="http://www.lispworks.com/documentation/HyperSpec/Body/f_pn.htm">pathname</a> foo))
#P"/Users/hans/blah-5OEJELG2.txt"</pre>

      Here, a relative pathname was used in the template, which
      caused the file to be generated in the directory established
      by <a xmlns="" href="http://www.lispworks.com/documentation/HyperSpec/Body/v_defaul.htm">*default-pathname-defaults*</a>.
    </p>
    <p>
      Alternatively, the <code xmlns=""><a href="#*default-template*">*default-template*</a></code>
      special variable can be set to define a custom default template
      for generating names.
    </p>
  
  <h5 xmlns=""><a class="none" name="security">Security</a></h5>
    The TEMPORARY-FILE library does not directly address security
    issues.  The application that uses it needs to take additional
    measures if it is important that files created by one process
    cannot be accessed by other, unrelated processes.  This can be
    done by using the system dependent security mechanisms like
    default file permissions or access control lists.

  <h5>Dictionary</h5>


    <p xmlns="">[Function]<br><a class="none" name="open-temporary"><b>open-temporary</b> <i><clix:lambda-list xmlns:clix="http://bknr.net/clixdoc">&amp;rest open-arguments &amp;key template generate-random-string max-tries &amp;allow-other-keys</clix:lambda-list></i>
          =&gt;
          <i>stream</i></a><blockquote><clix:description xmlns:clix="http://bknr.net/clixdoc">
        <p xmlns="http://www.w3.org/1999/xhtml">
          Create a file with a randomly generated name and return the
          opened stream.  The resulting pathname is generated from
          <code xmlns=""><i>template</i></code>, which is a string
          representing a pathname template.  A percent sign (%) in
          that string is replaced by a randomly generated string to
          make the filename unique.  The default for
          <code xmlns=""><i>template</i></code> places temporary files in the
          <code xmlns=""><a href="#temporary-files">temporary-files</a></code> logical pathname host,
          which is automatically set up in a system specific manner.
          The file name generated from <code xmlns=""><i>template</i></code>
          is merged with <a xmlns="" href="http://www.lispworks.com/documentation/HyperSpec/Body/v_defaul.htm">*default-pathname-defaults*</a>,
          so random pathnames relative to that directory can be
          generated by not specifying a directory in
          <code xmlns=""><i>template</i></code>.
        </p>
        <p xmlns="http://www.w3.org/1999/xhtml">
          <code xmlns=""><i>generate-random-string</i></code> can be passed to
          override the default function that generates the random name
          component.  It should return a random string consisting of
          characters that are permitted in a pathname (logical or
          physical, depending on <code xmlns=""><i>template</i></code>).
        </p>
        <p xmlns="http://www.w3.org/1999/xhtml">
          The name of the temporary file can be accessed calling the
          <a xmlns="" href="http://www.lispworks.com/documentation/HyperSpec/Body/f_pn.htm">pathname</a>
          function on <code xmlns=""><i>stream</i></code>.  For convenience,
          the temporary file is opened on the physical pathname,
          i.e. if the <code xmlns=""><i>template</i></code> designate a
          logical pathname the translation to a physical pathname is
          performed before opening the stream.
        </p>
        <p xmlns="http://www.w3.org/1999/xhtml">
          In order to create a unique file name,
          <code xmlns=""><a href="#open-temporary">open-temporary</a></code> may loop internally up
          to <code xmlns=""><i>max-tries</i></code> times before giving up and
          signalling a
          <code xmlns=""><a href="#cannot-create-temporary-file">cannot-create-temporary-file</a></code> condition.
        </p>
        <p xmlns="http://www.w3.org/1999/xhtml">
          Any unrecognized keyword arguments are passed to the call to
          <a xmlns="" href="http://www.lispworks.com/documentation/HyperSpec/Body/f_open.htm">open</a>.
        </p>
      </clix:description></blockquote></p>
    <p xmlns="">[Macro]<br><a class="none" name="with-output-to-temporary-file"><b>with-output-to-temporary-file</b> <i><clix:lambda-list xmlns:clix="http://bknr.net/clixdoc">(stream &amp;rest args) &amp;body body</clix:lambda-list></i>
          =&gt;
          <i>pathname</i></a><blockquote><clix:description xmlns:clix="http://bknr.net/clixdoc">
        Create a temporary file using
        <code xmlns=""><a href="#open-temporary">open-temporary</a></code> with
        <code xmlns=""><i>args</i></code> and run <code xmlns=""><i>body</i></code>
        with <code xmlns=""><i>stream</i></code> bound to the temporary file
        stream.  Returns the pathname of the file that has been
        created.  See <code xmlns=""><a href="#open-temporary">open-temporary</a></code> for
        permitted options.
      </clix:description></blockquote></p>
    <p xmlns="">[Macro]<br><a class="none" name="with-open-temporary-file"><b>with-open-temporary-file</b> <i><clix:lambda-list xmlns:clix="http://bknr.net/clixdoc">(stream &amp;rest args &amp;key keep &amp;allow-other-keys) &amp;body body</clix:lambda-list></i>
          =&gt;
          <i>values</i></a><blockquote><clix:description xmlns:clix="http://bknr.net/clixdoc">
        Create a temporary file using
        <code xmlns=""><a href="#open-temporary">open-temporary</a></code> with
        <code xmlns=""><i>args</i></code> and run <code xmlns=""><i>body</i></code>
        with <code xmlns=""><i>stream</i></code> bound to the temporary file
        stream.  Returns the values returned by
        <code xmlns=""><i>body</i></code>.  By default, the file is deleted
        when <code xmlns=""><i>body</i></code> is exited. If a true value is
        passed in <code xmlns=""><i>keep</i></code>, the file is not deleted
        when the body is exited.  See
        <code xmlns=""><a href="#open-temporary">open-temporary</a></code> for more permitted
        options.
      </clix:description></blockquote></p>
    <p xmlns="">
      [Special variable]<br><a class="none" name="*default-template*"><b>*default-template*</b></a><blockquote><clix:description xmlns:clix="http://bknr.net/clixdoc">
        This variable can be set to a string representing the desired
        default template for temporary file name generation.  See
        <code xmlns=""><a href="#open-temporary">open-temporary</a></code> for a description of the
        template string format.
      </clix:description></blockquote></p>
    <p xmlns="">
      [Condition type]<br><a class="none" name="cannot-create-temporary-file"><b>cannot-create-temporary-file</b></a><blockquote><clix:description xmlns:clix="http://bknr.net/clixdoc">
        Signalled when an attempt to create unique temporary file name
        failed after the established number of retries.
      </clix:description></blockquote></p>
    <p xmlns="">
      [Condition type]<br><a class="none" name="invalid-temporary-pathname-template"><b>invalid-temporary-pathname-template</b></a><blockquote><clix:description xmlns:clix="http://bknr.net/clixdoc">
        Signalled when the <code xmlns=""><i>template</i></code> argument to
        <code xmlns=""><a href="#open-temporary">open-temporary</a></code> does not contain a valid
        template string.  The template string must contain a percent
        sign, which is replaced by the generated random string to
        yield the filename.
      </clix:description></blockquote></p>
    <p xmlns="">
      [Condition type]<br><a class="none" name="missing-temp-environment-variable"><b>missing-temp-environment-variable</b></a><blockquote><clix:description xmlns:clix="http://bknr.net/clixdoc">
        (Windows only) Signalled when the TEMP environment variable is
        not set.
      </clix:description></blockquote></p>
    <p xmlns="">
      [Logical Pathname Host]<br><a class="none" name="lp-host-temporary-files"><b>temporary-files</b></a><blockquote><clix:description xmlns:clix="http://bknr.net/clixdoc">
        This logical pathname host defines where temporary files are
        stored by default.  It is initialized in a suitable system
        specific fashion: On Unix and Unix-like systems, the directory
        specified in the TMPDIR environment variable is used.  If that
        variable is not set, /tmp is used as the default.  On Windows,
        the directory specified in the TEMP environment variable is
        used.  If it is not set, a
        <code xmlns=""><a href="#missing-temp-environment-variable">missing-temp-environment-variable</a></code> error
        is signalled.
      </clix:description></blockquote></p>


<h4><a class=none name="modifying">Modifying the file system</a></h4>

<p><br>[Function]
<br><a class=none name="copy-file"><b>copy-file</b> <i> from to <tt>&amp;key</tt> overwrite</i> =&gt; |</a>

<blockquote><br>
Copies the file designated by the non-wild <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_p.htm#pathname_designator">pathname designator</a> <code><i>from</i></code> to the
file designated by the non-wild <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_p.htm#pathname_designator">pathname designator</a> <code><i>to</i></code>.  If <code><i>overwrite</i></code> is <em>true</em> (the default is <code>NIL</code>)
overwrites the file designtated by <code><i>to</i></code> if it exists.
</blockquote>

<p><br>[Function]
<br><a class=none name="copy-stream"><b>copy-stream</b> <i> from to <tt>&amp;optional</tt> checkp</i> =&gt; |</a>

<blockquote><br> Copies into <code><i>to</i></code> (a stream)
from <code><i>from</i></code> (also a stream) until the end
of <code><i>from</i></code> is reached.  The streams should have the
same <a
href="http://www.lispworks.com/documentation/HyperSpec/Body/f_stm_el.htm">element
type</a> unless they are bivalent.  If <code><i>checkp</i></code> is
true (which is the default), the function will signal an error if the
element types aren't the same.
</blockquote>
<p><br>[Function]
<br><a class=none name="delete-directory-and-files"><b>delete-directory-and-files</b> <i> dirname<tt>&amp;key</tt> if-does-not-exist</i> =&gt; |</a>

<blockquote><br>
<p>
Recursively deletes all files and directories within the directory
designated by the non-wild <a href="http://www.lispworks.com/documentation/HyperSpec/Body/26_glo_p.htm#pathname_designator">pathname designator</a> <code><i>dirname</i></code> including
<code><i>dirname</i></code> itself.  <code><i>if-does-not-exist</i></code> must be one of <code>:ERROR</code> or <code>:IGNORE</code>
where <code>:ERROR</code> (the default) means that an error will be signaled if the directory
<code><i>dirname</i></code> does not exist.
</p>
<p>
  <b>Warning:</b> this function <em>might</em> remove files from outside the
  directory, if the directory that you are deleting contains links to
  external files.  This is currently fixed for SBCL and CCL.
</p>
</blockquote>

<h4>The <code>PATH</code> package</h4>

<p><br>[Package]
<br><a class=none name="package-path">(defpackage <b>path</b>)</a>

<blockquote>
Provides a set of short names for commonly used pathname manipulation
functions (these are all functions from the <code>cl-fad</code>
package which are being exported under different names):
<dl>
  <dt><code>dirname</code></dt> <dd><a href="#pathname-as-directory">pathname-as-directory</a></dd>
  <dt><code>basename</code></dt> <dd><code>cl:file-namestring</code></dd>
  <dt><code>-e</code></dt> <dd><a href="#file-exists-p">file-exists-p</a></dd>
  <dt><code>-d</code></dt> <dd><a href="#directory-exists-p">directory-exists-p</a></dd>
  <dt><code>catfile</code></dt> <dd><a href="#merge-pathnames-as-file">merge-pathnames-as-file</a></dd>
  <dt><code>catdir</code></dt> <dd><a href="#merge-pathnames-as-directory">merge-pathnames-as-directory</a></dd>
  <dt><code>rm-r</code></dt> <dd><a href="#delete-directory-and-files">delete-directory-and-files</a></dd>
  <dt><code>=</code></dt> <dd><a href="#pathname-equal">pathname-equal</a></dd>
  <dt><code>absolute-p</code></dt> <dd><a href="#pathname-absolute-p">pathname-absolute-p</a></dd>
  <dt><code>relative-p</code></dt> <dd><a href="#pathname-relative-p">pathname-relative-p</a></dd>
  <dt><code>root-p</code></dt> <dd><a href="#pathname-root-p">pathname-root-p</a></dd>
</dl>
</blockquote>


<br>&nbsp;<br><h3><a class=none name="ack">Acknowledgements</a></h3>

The original code for this library was written by Peter Seibel for his
book <a href="http://www.gigamonkeys.com/book/"><em>Practical Common
Lisp</em></a>. I added some stuff and made sure it worked properly on
Windows, specifically with CCL.  Thanks to James Bielman, Maciek
Pasternacki, Jack D. Unrue, Gary King, and Douglas Crosher who sent
patches for OpenMCL, ECL, ABCL, MCL, and Scieneer&nbsp;CL.

<p>
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